In 1832 the electric telegraph was invented by Morse, though he did not patent it until 1837. The influence of the electric telegraph on subsequent history has been so great that the influence of no contemporary invention can reasonably be declared to be greater. As with many other inventions, one is tempted to wonder why it had not been invented before; for the fact that electricity could be sent along a conductor and made to cause motion at the other end had been known since Guericke had demonstrated the fact in the closing years of the seventeenth century. The original invention of the electric telegraph is claimed by some for Henry, who had a wire run between his house and his laboratory at Princeton, over which he sent messages, by opening and closing the circuit and thereby actuating an electro-magnet at the receiving end. The first machine to put Faraday's discovery of magneto-electric induction to practical use was invented by Pixii in France in 1832, and exhibited before the Academy of Sciences. It consisted of a powerful magnet that was made to revolve with great rapidity before a bar of soft iron that had wrapped around it a coil of insulated wire about 3,000 feet long. The north and south poles taking position in succession in front of the coil, currents were induced that alternated in direction, twice in each revolution. If a man grasped two wires in the circuit he received a series of sharp electric shocks; but such effects as decomposing water that were produced by the continuous currents of Voltaic batteries could not be produced by these alternating currents. To secure such effects, Siemens and others made machines in which the magnet in the form of a U was stationary, two coils of wire revolved in front of the poles, and a two-part "commutator" was used. When this was placed on the axle, and the axle was revolved, the change in direction of the current was obviated, though a smooth and uniform current was not produced. The reason was that the current fell to zero twice in each revolution. The magneto-electric machine, as it was called, remained virtually in this form for many years. It was not sufficiently effective or efficient to be of much practical usefulness in any art, and was considered more of a scientific toy than a machine of serious importance. Still, the probability was realized by many investigators that a new discovery or invention might be made at any moment, that would put it in the forefront of the useful inventions of the age. (The invention was not made till 1862; it was made by Pacinnotti in Italy and will be mentioned later.)